insert elements into an array, keeping it sorted.

sorted-insert-binary-search.js

function binarySearch(arr, target, left, right, closest=-1) {
    if(arr.length <=0) return 0;

    const mid = Math.floor((left+right)/2);

    closest = arr[mid] < target ? mid+1 : mid;

    if(left < right) {
        if(arr[mid] < target) {
            return binarySearch(arr, target, mid+1, right, closest);
        }else if(arr[mid] > target) {
            return binarySearch(arr, target, left, mid-1, closest);
        }
    }

    return closest;

}

function findValue(haystack, needle) {
    return binarySearch(haystack, needle, 0, haystack.length);
}

function insertValue(arr, value) {
    const idx = findValue(arr, value);
    arr.splice(idx,0,value);
    return arr;
}

let arr = [];

[3,6,1, 0, 10, 9, 4, -1, -5, 20, 19, 4, 3, 2, 7].forEach(value => {
    insertValue(arr, value);
    console.log(arr);
});